Note: Descriptions are shown in the official language in which they were submitted.
CA 02623707 2008-03-07 2 1 DESCRIPTION BACKGROUND OF THE INVENTION TECHNICAL FIELD The invention relates to the two-dimensional profile of the tongue member and the groove member of a floorboard forming an hereafter named floorboard system. The tongue-and- groove profiles of the present invention, while considering accuracy, ease of installation and retaining force, allow to easily separate floorboards that have already been assembled without damaging their tongue-and-groove joints. Traditionally, the tongue-and-groove profiles are designed to insure accuracy, ease of installation of the floorboards and to maintain a strong tension once installed as to avoid some unwanted separation. The floorboards are made of cellulose rich materials that make them react to changes in humidity index. In high humidity environment, humidity intake makes the floorboards to swell. Such reaction may cause excess tension between tongue-and-groove joints of assembled floorboards, preventing ease of disassembling. Ease of disassembling is required since floorboards are traditionally packed in 4 layers of 3 or 4 wide assembled panels. Those need to be disassembled at the point of installation. If excessive force is used to separate swollen floorboards, it may cause permanent damage to them and/or demand additional precautions that result in an increase in disassembling time. The time of disassembling should be kept under '/2 second per set of two assembled floorboards. At the point of installation, the criteria to reject a batch of floorboards by a contractor or the installers are any reasons that could affect the quality of the final floor covering installation, create excessive waste of floorboard material or slow down the installation itsel If the floorboards in a package are too tightly held together, disassembling them may requires more time, effort and increase the risk of damaging them by the installer. In many cases, it leads to the rejection of an entire batch of floorboards. One way to avoid the problem would be to manufacture floorboards with a thinner tongue or a wider groove. In a situation where humidity is not a problem, the accuracy of installation or maintaining a strong tension preventing floorboards separation once installed could not be insured. Furthermore, varnishing and staining widely used processes demand prior assembling of floorboard in order to form a large and stable surface usually 4 feet wide in North America. Such large surface allows effective use of sanding techniques prior to the application of the varnish or the stain. To insure a quality processing, the floorboards must be kept tightly assembled. At the end of the varnishing process, sections of floorboards are again disassembled in sections of 3 or 4 panels wide for packaging. They are left assembled to minimize package volume. A typical package or process surface is around 20 square feet (2 square meters) and contains around 40 preassembled floorboards. CA 02623707 2008-03-07 3 I Overall, a floorboard can be assembled and disassembled 2 to 3 times prior to its final installation without causing any permanent damages to the floorboard or the tongue-and- groove profile. The two-dimensional floorboard profiles of the tongue member and the groove member of the invention allow ease of disassembling without sacrificing the ease of assembly and holding tension once installed. PRIOR ART Tongue-and-groove members joining adjacent floorboards have long time been presented in multiple patents, for example U.S. Patents No. 4,095,913 dated 1978. Such patents presents tongue-and-groove profiles designed for an only one time assembly and mostly to prevent distortion of installed panels when excess humidity makes panels, and/or floorboards, to swell and expand. Multiple assembly and disassembly of said panels are likely to cause permanent damage to the tongue or groove profile or even to the floorboards. A key feature of the present invention is that the groove member asymmetrical profile has a gradual opening on its upper area and the tongue member asymmetrical profile has a gradual thickening on its lower area. Not to be confused with U.S. Patents No. 6,581,351 where the groove is symmetrically cut at an angle, giving a progressive closing of it and the tongue is symmetrically cut at an angle, giving a progressive thickening of it. The design is to prevent the squeaking noise once the floor covering has been installed. The present invention is to ease the separation of floorboards prior to final installation. For the present invention, grooves and tongues have a retaining contact force on 80% of a flat (non tapered) surface. Less than 20% of the surface has a non contact section with no retaining force. A key feature of the present invention is the tongue-and-groove unsymmetrical profile used to ease the disassembly when torsion forces are applied in one rotation. While the assembly retaining force is magnified when torsion force are applied in the opposite rotation. Not to be confused with U.S. Patents No. 5,618,602 that presents an asymmetrical tongue member profile. The groove member profile is symmetrical. The opening area caused by the junction of both profiles is about providing a space between the tongue-and-groove for glue and having a waterproofjoint. It is related to laminar flooring and not to solid wood floorboards. Canadian Patents No. 2466614 presents a German invention that pushes the unsymmetrical profile to a point that demands complex manufacturing techniques. Despite the simplicity mentioned, as quoted: The object underlying the invention is to provide a panel in which a reliable connection between adjacent panels can be produced by simple means. In this context, "simple means" signifies, in particular, simple tools, the least critical tolerances possible in manufacture, and also the lowest possible demands on the material panel.", the Canadian patents No. 2466614 present a complex profile making it difficult to manufacture. This Canadian patents No. 2466614 uses a locking mechanism that applies constant pressure against the upper joint surface and does not allow the disassembly of floorboards when tension is applied in the plan parallel to the floorboards. In other words, disassembly imposes a rotation of both floorboards. This Canadian patents No. 2466614 apply only to engineered flooring as the geometry of the tongue will not resist insertion pressure and will most likely brake down for floorboard made of wood. Floorboards with tongue-and-groove designed to allow ease of disassembling as with U.S. Patents No. 7,124,549 are usually intended for floating type of floor covering. Their interlocking tongue-and-groove are precisely cut to insure a tight assembly of the floorboards without the need of nail or glue, and are designed as to allow ease of disassembling when the CA 02623707 2008-03-07 4 1 floor covering is to be reused elsewhere or need to be repaired. Those floorboards may be nailed and glued but then the tongue-and-groove design brings no advantages. The present invention is not meant to provide a reusable type of floorboard but rather to provide a disassembling system prior to installation of the floorboards that has no more use once installed since the floorboards are glued or nailed in place and the installation is final. SUMMARY OF THE INVENTION Traditional floorboards usually nailed or glued at installation have their tongue-and-groove designed as to insure uniformity of the floor covering once installed and to insure a final tight assembly. None of those traditional floorboards are designed to allow ease of separation prior to installation. If those floorboards tongue-and-groove were made to ease separation, they could not insure a tight assembly. The present invention seeks to eliminate or at least mitigate the disadvantages of the prior art and has for objective to provide floorboard with tight assembly once installed and for factory's varnishing process while remaining easy to separate for the contractor who install the floorboard as floor covering. The floorboards are designed for a traditional nailed or glued installation. In order to meet those contradictory requirements, the present invention provides a tongue- and-groove design that insure a firm grip and a tight assembly of floorboards to insure quality of processing at varnishing, while allowing ease of disassembling by a simple rotational movement of the floorboards to ease the work of the installer without modifying the traditional way of installation. For this purpose, the floorboard system consists of : i. A tongue member with a reduction in its thickness located in the lower section of the tongue, and ii. A groove member with an increase in its wideness located in the upper section of the groove. All of which would result in a: i. System wherein a manual torsion applied, bending the tongue-and-groove members upward allow ease of disassembly of both said members. ii. System wherein the upper surfaces of the tongue-and-groove are parallel and include a micro-V at the junction of the two floorboard members. Preferably, the present system allows a constant case of disassembly whatever the humidity index or humidity intake of the floorboards. Additionally, the present system allows a better stability and uniformity of the floorboards assembling for the varnishing and staining process. Additionally, the present system allows a better stability of the floorboards assembly for the sanding process. Additionally, the present system allows a better accuracy of the sanding process to provide a more uniform micro-V CA 02623707 2008-03-07 1 Additionally, the present system allows reducing rejects due to short floorboards separation during the sanding process. Additionally, the present system allows an easy disassembling of floorboards in sections of 3 5 to 4 panels prior to packaging. Additionally, the present system allows an easy disassembling of floorboards sections of 3 to 4 panels into individual floorboards prior to installation. Additionally, the present system allows a better uniformity and stability of the floorboards finishing micro-V. Additionally, the present system allows a quicker installation process as the tongue-and- groove profile permit an easy insert of the tongue into the groove for the first 0.040" prior to the final tightening of the two floorboard sections. Additionally, the present system allows for a tight and stable floor covering installation even if a lack of surrounding humidity would make the floorboards to dry and contract. Additionally the present system allows maintaining a constant leveling between floorboards forming the floor covering, once installed. Various profiles, features, aspects and advantages of the present invention will become clearer with the following description and accompanying drawings of a preferred embodiment of the invention. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 illustrates a sectional view of the tongue-and-groove profile of a first embodiment of the invention, specifically a groove member profile presenting a two-step opening on its upper area and a tongue member profile presenting a two-step thickening on its lower area. Figure 2 illustrates, via a sequence of 4 images, the disassembly action when expose to torsion force bending upward. Figure 3 illustrates the retaining action when expose to torsion forces bending downward and retaining action when expose to tangential forces. Figure 4 illustrates the tongue profile with its shaped knife, negative profile. Figure 5 illustrates the groove profile with shaped knife, negative profile. Figure 6 illustrates the sectional view of a secondary profile of figure 1, specifically a groove member profile presenting a two-step opening on its both upper and lower areas or a tongue member profile presenting a two-step thickening on its both upper and lower areas. CA 02623707 2008-03-07 , . 7 6 1 DESCRIPTION OF THE PREFERRED EMBODIMENT Embodiments of the present invention provide floorboard, more specifically the profile of the tongue-and-groove members that allow ease of disassembly. Figure 1 shows the preferred tongue-and-groove members side view profile. Figure 2 shows the sequential movement of the tongue-and-groove members from interconnection to disassembly when expose to torsion forces. Figure 3 shows the stability of the tongue-and-groove members when exposed to opposite torsion forces or tangential forces. The floorboard I shown on figure 1 is constructed of solid wood with the top surface 3 and bottom surface 4 parallel to each others. The tongue la includes a microspace 8a on its lower outer section. The precision in alignment 27 between surface 3 and surface 4 is less than 0.005 in. The preferred length 14 of the microspace 8a represents 15% to 30% of the length of the tongue 15. The preferred reduction in the tongue thickness 16 represents 5% to 20% of the thickness of the tongue 17. The preferred transition angle 12 is 10 to 50 degrees with respect to the surface of the floorboard. The floorboard 2 shown on figure 1 is constructed of solid wood with the top surface 5 and bottom surface 6 parallel to each others. The groove 2a includes a microspace 9a on its upper outer section. The preferred length 18 of the microspace 9a represents 15% to 30% of the length of the groove 19. The preferred increase in the groove thickness 20 represents 5% to 20% of the thickness of the groove 21. The preferred transition angle 13 is 10 to 50 degrees with respect to the surface of the floorboard. The combination of the tongue la microspace 8a and the groove 2a microspace 9a allows both floorboard members I and 2 to slightly bend upward when torsion forces 10, 11a and 11b are applied. Figure 2 shows the dynamic effect on the tongue member la and groove member 2a when exposed to the said torsion forces 10, 11 a and 11 b. Reversely, Figure 3 shows the static effect on the tongue member la and groove member 2a when exposed to the reverse torsion forces 22, 23 and 24, where reverse torsion is in reference to torsion forces 10, 11 a and 11 b. Figure 3 also shows the retaining effect on the tongue member 1 a and groove member 2a when exposed to the tangential forces 25 and 26. The upper surface junction of the floorboard 1 and 2 includes a"micro-V" 7. Even thought presented in the preferred embodiment, the concept of this invention remain valid without a "micro-V" 7. Figure 4 shows the details dimensions of the shaped knife 28 for cutting the profile of the tongue 1 a. Figure 5 shows the details dimensions of the shaped knife 29 for cutting the profile of the groove 2a. Figure 6 shows alternatives where the tongue lb includes one microspace 8b on its lower outer section with no microspace on the groove 2b. The groove 2c includes one microspace 9c on its upper outer section with no microspace on the tongue 1c. The tongue 1d includes two microspaces 8d 1 and 8d2 on its outer section witll no microspace on the groove 2d. The groove 2e includes two microspaces 9e1 and 9e2 on its outer section with no microspace on the tongue 1 e. The combination of the dual microspaces allows both members, the tongue I and groove 2, to slightly bent upward or downward when either torsion forces 10, 1 la and 1 l b or torsion forces 22, 23 and 24 are apply. The end results are the ease of disassembly of both floorboard members I and 2 with torsion forces applied in any direction. CA 02623707 2008-03-07 7 1 Although the present invention is presented in terms of a floorboard made of solid wood, the embodiments are not intended to limit the material to solid wood, whereas the terms "solid wood" can be replaced but not limited to any other wood derivatives such as HDF, MDF, plywood, and engineering panels. Additionally, Although the present invention is presented with respect to floorboard, the embodiments are not intended to limit the application to floorboard where the terms tongue member and groove member of the present invention may be utilized in any application in which it is desired to have a tongue-and-groove joint, whereas the terms "floorboard" can be replaced but not limited to wood panels, floor covering, flooring systems, wood board, wooden floor units and building boards. Although the foregoing describes the invention in terms of embodiments, the embodiments are not intended to limit the scope of the claims. Rather, the claims are intended to cover all modifications and alternative printing techniques falling within the spirit and scope of the invention, and are limited only by the plain meaning of the words as used in the claims. 30 40 50
